New Delhi: The war of words between BJP and Congress over the controversy surrounding Home Minister P Chidambaram in 2G spectrum row escalated on Saturday with the main opposition party saying his place was in the same cell in Tihar jail where former Telecom Minister A Raja is lodged.

Upping the ante, BJP leader Yashwant Sinha also demanded that the court should order a probe into the "role" of both Prime Minister and Chidambaram, when he was the Finance Minister, during the controversial 2G spectrum allocation.

Congress said Sinha's swipes at Chidambaram were highly condemnable with its senior leader Digvijay Singh alleging that the Home Minister was being targeted by the RSS after he acted against Sanghi terror.

"Chidambaram is a man of integrity, a man of competence and there is no question of any charges against him," the AICC General Secretary said while putting up a strong defence of his party colleague.

Singh said "BJP should look into its own "backyard" first before leveling allegations against others... particularly when it is against an able and competent Minister like Chidambaram."

He said it is unjustified and incorrect to level allegations against Chidambaram in this case.

Earlier, Sinha, a former Finance Minister, said, "There is so much evidence that has come out against P Chidambaram in the 2-G spectrum case that for CBI to say in court now that he is not guilty would be laughable. Chidambaram's place is in the same cell in Tihar jail in which A Raja has been lodged."

Sinha was equally scathing against the Prime Minister, charging he was fully in the know of the developments in the 2-G Spectrum allocation all along. Sinha said the Prime Minister had earlier defended A Raja but stopped doing so when he was sent to jail.

"When Chidambaram is sent to jail, the Prime Minister will stop defending him too. Then he will only defend himself. And when his government goes in the wake of this scam, then it will become difficult for him to defend himself," Sinha said.

He alleged that the Prime Minister was "aware and fully complicit" in the scam as Raja had kept him informed.

The former Finance Minister, who is also a member of the Joint Parliamentary Committee probing the spectrum case, said he had an inkling of Chidambaram's involvement all along and what has come to light now is not a surprise.

"What is there in the note is not new for some of us. Chidambaram's role has always been under the needle of suspicion," he said, adding that he was a member of the JPC.

Sinha insisted that the Finance Ministry note confirms BJP's suspicion as now even the Finance Minister is saying what the opposition has alleged till now.

He maintained that the documents show that Chidambaram had "completely abandoned" the initial stand taken by the Finance Ministry on the 2-G spectrum issue. The ministry officials had reportedly suggested that spectrum should be auctioned.

"The entry fee of 2001 will not be valid in 2008. And by then spectrum had also become a scarce commodity and should have been 'market-discovered'," Sinha said.

BJP maintained that on July 4, 2008 Chidambaram apprised the Prime Minister of his conclusion on this issue. The party alleged that Chidambaram left aside his ministry's stand and went with the Telecom Ministry's opinion.

"The consensus which Chidambaram was talking about was actually the DOT opinion," Sinha said.

Asked if he was charging Chidambaram with not just procedural lapses but also "criminal culpability", Sinha answered in the affirmative.

He felt his party should have attacked Chidambaram harder than it has till now.

"I would like to say with all due regard to my BJP colleagues that the party has till now tread a soft line against Chidambaram," Sinha said.

Attacking the Prime Minister, Sinha said, "What kind of a PM do we have who is told to keep off by Raja and he does so". He said somebody should ask the Prime Minister why he wanted to be kept at an "arm's length" on this issue.

He defended NDA government's Telecom policy, saying it had gone for a first-come-first serve policy at that time as there were only two players in the fray at that time and spectrum was not scarce then.

Defending National Telecom Policy-1999, Sinha said at that time if the government had gone for auctions, it would not have got a "single farthing".

"Duopoly was ended and multipoly brought in later... It is a complete mis-statement to say that there was a loss of revenue," Sinha said.

He insisted that Chidambaram should be tried based on "prima facie guilt" as CVC has inquired into the 2-G spectrum issue and now the CBI in inquiring into it.